1-(substituted phenyl) tetrazolinone derivatives, their preparation and their use as herbicides

Abstract: Tetrazolinones of the formula (I) wherein X represents chloro, Y represents hydrogen atom, chloro, or methyl, R¹ represents ethyl or n-propyl, and R² represents cyclopentyl or cylohexyl, with the proviso that the total of the carbon atoms of R¹ arid R² is 7 or 8, a process for their preparation, and the use of the new compounds as herbicides, especially against paddy-weeds.

Description: The present invention relates to novel tetrazolinones, to a process for the preparation thereof, and to their use as paddy-herbicides. It has already been disclosed that tetrazolinone derivatives have herbicidal properties (see U.S. Patents Nos. 4,956,469; 5,003,075 and 5,019,152 or the corresponding European Applications EP-A-146 279 and EP-A-202 929). The results of a quantitative structure-activity relationships (QSAR) study in this series of herbicidal 1-phenyl-4-carbamoyl-5(4)-tetrazolinone derivatives have also be reported (see Proc. Br. Crop Prot. Conf.-Weeds (1987), pp. 249-255); this study includes the three closely related compounds designated as comparative compounds C-1, C-2 and C-3 in the "Examples" section of the present specification (see below). Further, there have been described certain 1-phenyl-4-carbamoyl-5(4)-tetrazolinones as herbicides which essentially differ from those of the present invention in that they cannot bear a cycloalkyl substituent on the carbamoyl moiety (see the Art.54(3)EPC-documents EP-A-571 854, EP-A-571 855, EP-A- 572 855 and EP-A-578 090). There have now been found novel tetrazolinones of the formula (I) wherein X represents chloro, Y represents hydrogen atom, chloro, or methyl, R 1 represents ethyl or n-propyl, and R 2 represents cyclopentyl or cylohexyl, with the proviso that the total of the carbon atoms of R 1 and R 2 is 7 or 8. The compounds of the formula (I) can be obtained by a process in which a) compounds of the formula (II) wherein X and Y have the same meanings as mentioned before, are reacted with compounds of the formula (III) wherein R 1 and R 2 have the same meanings as mentioned above, and hal is an eliminating group such as chlorine or bromine, in the presence of inert solvents, and if appropriate, in the presence of an acid binder. The novel tetrazolinones (I) exhibit powerful herbicidal properties, in particular against paddy-field weeds. While the compounds of the formula (I), according to the invention, generically fall within the scope of the aforementioned U.S. and corresponding EP patent rights, the compounds of the formula (I) have not been specifically disclosed in these references. And, surprisingly, the compounds of the formula (I) exhibit a substantially much greater herbicidal action against paddy-weeds than those specifically known from the references. Among the compounds of the formula (I), according to the invention, preferred compounds are those in which X represents chloro, Y represents hydrogen atom, or methyl, R 1 represents ethyl or n-propyl, and R 2 represents cyclopentyl or cyclohexyl , with the proviso that the total of the carbon atoms of R 1 and R 2 is 7 or 8. Specifically, the following compounds, in addition to the compounds mentioned in the Examples, may be mentioned hereinafter: 1-(2-chlorophenyl)-4-(N-cyclopentyl-N-ethylcarbamoyl)-5(4H)-tetrazolinone, 1-(2-chlorophenyl)-4-(N-cyclopentyl-N-n-propylcarbamoyl)-5(4H)-tetrazolinone, 1-(2-chlorophenyl)-4-(N-cyclohexyl-N-ethylcarbamoyl)-5(4H)-tetrazolinone, 1-(2-chloro-6-methylphenyl)-4-(N-cyclopentyl-N-propylcarbamoyl)-5(4H)-tetrazolinone, and 1-(2-chloro-6-methylphenyl)-4-(N-cyclohexyl-N-ethylcarbamoyl)-5(4H)-tetrazolinone. If use is made, in the above-mentioned process a), of 1-(2-chlorophenyl)-5(4H)-tetrazolinone and N-cyclohexyl-N-ethylcarbamoyl chloride, as the starting materials for example, the reaction can be expressed by the following reaction equation: In the process a) according to the invention, the starting compounds of the formula (II) mean compounds based on the above definition of X and Y, preferably compounds based on the above preferred definitions of X and Y. The compounds represented by the general formula (II) can be prepared in the manner similar to that described in "The Journal of Organic Chemistry", Vol. 45, No. 21, 1980, pages 5130 - 5136 or "The Journal of American Chemical Society", Vol. 81, No. 7, 1980, pages 3076 - 3079. As examples of the compounds represented by the general formula (II), there may be mentioned the following compounds: 1-(2-chlorophenyl)-5(4H)-tetrazolinone, 1-(2-chloro-6-methylphenyl)-5(4H)-tetrazolinone, and 1-(2,6-dichlorophenyl)-5(4H)-tetrazolinone. In the process a) according to the invention, the starting compounds of the formula (III) mean compounds based on the above definition of R 1 and R 2 , preferably compounds based on the above preferred definitions of R 1 and R 2 . The compounds of formula (III) are well known in the field of organic chemistry. As specific examples thereof, there may be mentioned: N-cyclopentyl-N-ethylcarbamoyl chloride, N-cyclopentyl-N-n-propylcarbamoyl chloride, and N-cyclohexyl-N-ethylcarbamoyl chloride. In carrying out the process a) mentioned above, use may be made, as suitable diluents, of any inert organic solvents. Examples of such diluents are aliphatic, cycloaliphatic and aromatic, optionally chlorinated, hydrocarbons such as pentane, hexane, cyclohexane, petroleum ether, ligroin, benzene, toluene, xylene, dichloromethane, chloroform, carbon tetrachloride, 1,2-dichloroethane, chlorobenzene or dichlorobenzene; ethers such as diethyl ether, methyl ethyl ether, diisopropyl ether, dibutyl ether, dioxane, dimethoxyethane (DME), tetrahydrofuran (THF) or diethylene glycol dimethyl ether (DGM); nitriles such as acetonitrile or propionitrile; acid amides such as dimethyl formamide (DMF), dimethyl acetamide (DMA), N-methylpyrrolidone, 1,3-dimethyl-2-imidazolidinone or hexamethylphosphoric triamide (HMPA); sulfones and sulfoxides such as dimethyl sulfoxide (DMSO) or sulfolane; and bases such as pyridine. The above-mentioned process a) may be carried out in the presence of acid binder, and as the acid binder may be mentioned, for example, inorganic bases including hydroxides, carbonates, bicarbonates, alcoholates, and hydrides of alkali metals, such as sodium hydrogen carbonate, potassium hydrogen carbonate, sodium carbonate, potassium carbonate, lithium hydroxide, sodium hydroxide, potassium hydroxide, calcium hydroxide, sodium methoxide, potassium methoxide, potassium tert-butoxide, lithium hydride, sodium hydride or potassium hydride; inorganic amides of alkali metals such as lithium amide, sodium amide or potassium amide; and organic bases including tertiary amines, dialkylaminoanilines and pyridines, such as triethylamine, 1,1,4,4-tetramethylethylenediamine (TMEDA), N,N-dimethylaniline, N,N-diethylaniline, pyridine, 4-dimethylaminopyridine (DMAP), 1,4-diazabicyclo[2,2,2]octane (DABCO) or 1,8-diazabicyclo[5,4,0]undec-7-ene (DBU). Furthermore, use may be made of organic lithium compounds such as, for example, methyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, phenyl lithium, dimethyl copper lithium, lithium diisopropyl amide, lithium cyclohexylisopropyl amide, lithium dicyclohexyl amide, n-butyl lithium·DABCO, n-butyl lithium·DBU or n-butyl lithium·TMEDA. In the above-mentioned process a), the reaction temperature can be varied within a substantially wide range. In general, the reaction is carried out at a temperature of from about -30°C to about 200°C, preferably from about -20°C to about 130°C. Further, the reaction is preferably carried out under normal pressure, although it is also possible to employ a higher or reduced pressure. When the above-mentioned process a) is carried out, use may be made, for example, of 1.0 to 1.2 mols of the compound of the formula (III) in a diluent such as acetonitrile, for example, per 1 mol of the compound of the formula (II) in the presence of 1 to 1.2 mols of an acid binder to obtain the desired compound. The compounds represented by the general formula (I) according to the present invention can be used as herbicides for controlling paddy weeds. Further, it has been discovered that a specially high herbicidal activity can be exhibited by herbicidal mixed compositions comprising, as active components, the compounds represented by the general formula (I) according to the present invention, together with at least one of the members selected from the group consisting of herbicidally active sulfonamides, herbicidally active pyrazols, herbicidally active propionanilides, herbicidally active triazines, herbicidally active carbamates, herbicidally active diphenylethers, and herbicidally active acid amides. Surprisingly, the herbicidal mixed compositions according to the present invention have been found to exhibit herbicidal effects substantially higher than the sum of the herbicidal effects that can be exhibited individually by the herbicidally active, respective components and, as the result, the concentration of each of the active compounds can be substantially reduced when practicing weed control operations, while at the same time, a wide herbicidal spectrum can be obtained. Further, the herbidical compositions according to the present invention have been found to expand the period of application time and, for example, in paddy rice cultivation, and exhibit excellent herbicidal effects for a period of from early stage of weed-emergence to weed-growing stage, with prolonged duration of activity and excellent residual effect, as well as phytotoxicity-free, excellent herbicidal effects on rice plant. As the specific examples of the herbicidal sulfonamides to be employed in the present herbicidal mixed compositions may be mentioned, for example, N-2-biphenylylsulfonyl N'-(4,6-dimethoxy-1,3,5-triazin -2-yl) urea, ethyl 5-[3-(4,6-dimethoxypyrimidin -2-yl)ureidosulfonyl]-1-methylpyrazole-4-carboxylate, methyl 2-[3-(4,6-dimethoxypyrimidin -2-yl)ureidosulfonylmethyl] benzoate, 3-(4,6-dimethoxy-1,3,5-triazin -2-yl)-1-[2-(2-methoxyethoxy)phenylsulfonyl] urea, N-(2-chloroimidazole[1,2-a]pyridin -3-yl-sulfonyl)-N'-(4,6-dimethoxy-2-pyrimidyl) urea, N'-(4,6-dimethoxypyrimidin -2-yl)-N''-(4-methylphenylsulfonylamino)-N'''-(4-ethoxycarbonyl-1-methylpyrazol -5-yl-sulfonyl) guanidine, and N-(2-cyclopropylcarbonylphenylsulfamoyl)-N'-(4,6-dimethoxypyridin -2-yl) urea. The above-mentioned compounds are also well known in the art The above-mentioned compounds are also well-known. (see Japanese Patent Publication No. 481/1984, Japanese Patent Laid-open Nos. 112379/1982, 56452/1982, 122488/1984, 38091/1989 and 70475/1989) As the specific examples of the herbicidally active pyrazoles to be employed in the present invention may be mentioned, for example, 4-(2,4,-dichlorobenzoyl)-1,3-dimethylpyrazol -5-yl-p-toluenesulfonate, 2-[4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol -5-yl] acetophenone, and 2-[4-(2,4-dichloro-m-toluoyl)-1,3-dimethylpyrazol -5-yloxy]-4-methylacetophenone. As the specific examples of the propionailides to be employed in the present invention may be mentioned, for example, 2-(β-naphthyloxy) propionanilide, and (RS)-2-(2,4-dichloro-m-tolyloxy) propionanilide. As the specific examples of the herbicidally active triazines to be employed in the present invention may be mentioned, for example, 2,4-bis(ethylamino)-6-(methylamino)-1,3,5-triazine, and 2-ethylamino-4-(1,2-dimethylpropylamino)-6-methylthiol-1,3,5-triazine. As the specific examples of the herbicidally active carbamates may be mentioned, for example, S-p-chlorobenzyl diethylthiocarbamate, S-1-methyl-1-phenylethyl piperidine-1-carbothioate, and S-benzyl 1,2-dimethylpropyl(ethyl) thiocarbamate, As the examples of the herbicidally active diphenylethers to be employed in the present invention may be mentioned, for example, 2,4,6-trichlorophenyl-4'-nitrophenylether, and 2,4-dichlorophenyl-3'-methoxy-4'-nitrophenylether. As the examples of the herbicidally active acid amides to be employed in the present invention may be mentioned, for example, (RS)-2-bromo-N-(α,α-dimethylbenzyl)-3,3-dimethylbutylamide. The above-mentioned active compounds are known herbicidally active compounds that are disclosed in "Pesticide Manual", 1991, published by The British Crop Protect Council. In the herbicidal mixed compositions according to the present invention, the mixing weight ratio of the active components may be varied in a relatively wide range. In general, use may be made, per one part by weight of the compounds represented by the general formula (I), of the herbicidal sulfonamides in the amount from 0.01 to 2 parts by weight, preferably from 0.05 to 1 part by weight; the herbicidally active pyrazoles in the amount of from 2.5 to 35 parts by weight, preferably from 3 to 15 parts by weight; the herbicidally active propionanilides in the amount of from 0.6 to 50 parts by weight, preferably from 2.0 to 28 parts by weight; the herbicidally active triazines in the amount of from 0.06 to 10 parts by weight, preferably from 0.15 to 6 parts by weight; the herbicidally active carbamates in the amount of from 3 to 15 parts by weight, preferably from 5 to 10 parts by weight; the herbicidally active diphenylethers in the amount of from 5 to 35 parts by weight, preferably from 7 to 15 parts by weight; and the herbicidally active acid amides in the amount of from 3.5 to 25 parts by weight, preferably from 4.0 to 10 parts by weight, respectively. The mixed compositions according to the present invention exhibit a strong herbicidal activity, therefore the above-mentioned compositions may be used as herbicidal compositions and they may be advantageously used particularly as selective herbicidal compositions for paddy rice. The herbicidal agents and mixed compositions according to the present invention can be applied, for example, to the following paddy weeds: Dicotyledons of the following genera : Polygonum, Rorippa, Rotala, Lindernia, Bidens, Dopatrium, Eclipta, Elatine, Gratiola, Lindernia, Ludwigia, Oenanthe, Ranunculus, Deinostema. Monocotyledons of the following genera : Echinochloa, Panicum, Poa, Cyperus, Monochoria, Fimbristylis, Sagittaria, Eleocharis, Scirpus, Alisma, Aneilema, Blyxa, Eriocaulon, Potamogeton. The herbicidal agents and mixed compositions according to the present invention can be applied specifically, for example, to the following paddy weeds in paddy fields: Botanical names Latin names Dicotyledons Rotala indica Rotala indica Koehne False pimpernel Lindernia Procumbens Philcox False loosestrife Ludwigia prostrata Roxburgh Largeleaf pondweed Potamogeton distinctus A. Benn American waterwort Elatine triandra Schk Dropwort Oenanthe javanica Monocotyledons Barnyard grass Echinochloa oryzicola vasing Monochoria Monochoria vaginalis Presl Matsubai Eleocharis acicularis L. Water chestnut Eleocharis Kuroguwai Ohwi Umbrella plant Cyperus difformis L. Mizugayatsuri Cyperus serotinus Rottboel Urikawa Sagittaria pygmaea Miq Narrowleaf waterplantain Alisma canaliculatum A. Br. et Bouche Bulrush Scirpus juncoides Roxburgh However, the application of the herbicidal agents and mixed compositions according to the present invention can be effected likewise also to other lowland weeds inhabiting paddy fields. The present herbicidal agent and mixed compositions can be prepared into any conventional formulations. As the formulations may be mentioned, for example, a liquid agent, an emulsion, a hydrated agent, a suspension, a powdery agent, a soluble powdery agent, a granular agent, a suspended emulsion concentration, and microcapsules in a polymeric substance. Those preparations can be prepared through well-known processes. The processes can be effected, for example, by mixing the active compounds with an extender, namely, with a liquid diluent and/or a solid diluent, and if required, with a surfactant, namely, with an emulsifier and/or dispensant and/or a foaming agent. In case of using water as an extender, for example, an organic solvent can also be used together as an auxiliary solvent. As liquid diluents may be mentioned, for example, aromatic hydrocarbons (such as xylene, toluene or alkylnaphthalene), chlorinated aromatic or chlorinated aliphatic hydrocarbons (such as chlorobenzenes, ethylene chlorides or methylene chloride), aliphatic hydrocarbons [such as cyclohexane or paraffins (for example, mineral-oil fractions, mineral or vegetable oils)], alcohols (such as butanol, glycol and ethers and esters thereof), ketones (such as acetone, methyl ethyl ketone, methyl isobutyl ketone or cyclohexanone), strong polar solvents (such as dimethylformamide and dimethyl sulfoxide), and water can also be mentioned as a liquid diluent. As solid diluents may be mentioned ammonium salts, and natural soily minerals (such as kaolin, clay, talc, chalk, quartz, attapulgite, montmorillonite, or diatomite) and soil synthetic minerals (such as highly dispersive silicic acid, alumina or silicate). And as solid carriers for granular agents there can be mentioned powdered and fractionated rocks (such as calcite, marble, pumice stone, meerschaum or dolomite), synthetic grains of organic or inorganic powders, and fine particles of organic substances (such as saw dust, coconut-shells, corn ear-stems, and tobacco stalks). As emulsifiers and/or foaming agents may be mentioned nonionic and anionic emulsifiers such as, for example, polyoxyethylene fatty acid esters, polyoxyethylene fatty alcohol ethers such as, for example, alkylaryl polyglycol ethers, alkyl sulfonates, alkyl sulfates, aryl sulfonates, and albumin hydrolysates. As dispersants, for example, lignin-sulfite waste liquor and methyl cellulose are suitable. Adhesives or stickers may also be used in the formulations in the form of powdery agent, granular agent, jambo agent, or emulsion, and as adhesives or stickers may be mentioned carboxy methyl cellulose, natural and synthetic polymers (such as gum arabic, polyvinyl alcohol, and polyvinyl acetate for example), natural phosphatides (such as cephalins and lecithins), and synthetic phosphatides. Further as additives may be used also mineral and vegetable oils. Colorants may also be used, and as such colorants may be mentioned inorganic pigments (such as, for example, iron oxide, titanium oxide and Prussian blue), and organic dyes such as, for example, alizarin dye, azo dye, and metallic phthalocyanine pigments, and further a trace amount of such elements as salts of iron, manganese, boron, copper, cobalt, molybdenum and zinc. The formulation contains generally 0.1 to 95% by weight, preferably 0.5 to 90% by weight of the active compound. In order to control weeds, the active compounds of the herbicidal agent and herbicidal composition according to the present invention can be used as such, or in the form of formulations thereof, and the mixture can be handled in the form of formulations or in the form of a tank-mixture. The active compound according to the present invention can be used as a mixture with other well-known active compounds, that is, with active compounds normally used for paddy fields such as, for example, bactericides, insecticides, plant-growth regulators, plant nutritive agents, soil conditioners, safener and any other herbicides. As the preferable examples, to the herbicidal compositions according to the present invention may be added, per 1 part by weight of the herbicidal sulfonamides, from 1 to 200 parts by weight, preferably from 2 to 100 parts by weight of safener such as 1-(α,α-dimethylbenzyl)-3-p-tolylurea, for example. The present active compounds can be used as such, as their formulations or as the use forms prepared therefrom by further dilution thereof, such as in the forms of ready-to-use solutions, emulsions, suspensions, powders, wettable powders, pastes and granules. They may be used in the customary manner, for example, by watering, spraying, atomising, dusting or scattering. The present active compounds can be used either in the pre-, or post-emergence period of plants. It is also possible to apply the active compounds into soil before the seeds of plants are sown. The concentration of active compound used in the present herbicidal agents can vary within a substantially wide range. It depends essentially on the nature of the desired effect. In general, the amounts used as a herbicide are from about 0.01 to about 10 kg of active compound per hectare, preferably from about 0.1 to about 2 kg/ha. The dosages of the present herbicidal mixed compositions may be varied within a substantial wide range, viz., from 0.1 to 5 kg/ha and preferably from 0.2 to 3 kg/ha in terms of the amount of active compounds. The preparation and the use of the active compounds according to the present invention are illustrated by the following examples. [Examples] Synthesis Examples: Example 1 1-(2-chlorophenyl)-5(4H)-tetrazolinone (2 g) and potassium carbonate (1.68 g) were suspended in acetonitrile (30 ml), followed by fifteen minute heating under refluxing. After cooling, N-cyclohexyl-N-ethylcarbamoyl chloride (2.31 g) was added to the reaction mixture, followed by a further five-hour heating under refluxing. The resulting mixture was filtered and the filtrate was evaporated under reduced pressure, and the resulting residue was subjected to a flush column chromatography (hexane:ethylacetate=5:2), to obtain the desired 1-(2-chlorophenyl)-4-(N-cyclohexyl-N-ethylcarbamoyl)-5(4H)-tetrazolinone (3.02 g) having a m.p. in the range of from 77.5 to 79.5°C. The compounds to be obtained by a process similar to the above-mentioned reaction procedures, together with the compound obtained in Example 1 are shown in Table 1. Example 2 (synthesis of intermediate compound) 2-chlorophenylisocyanate (7g) and trimethylsilylazide (7.9g) were mixed and refluxed for eight hours. The excessive trimethylsilylazide was distilled off under reduced pressure,and to the resulting residue there were added 40 ml of methanol. Thereafter, the solvent was distilled under reduced pressure to give crude product that was then subjected to a flush column chromatography ( hexane : ethylacetate = 2:1 ), to obtain the desired 1-(2-chlorophenyl)-5(4H)-tetrazolinone ( 7g ) having a melting point in the range of from 124.5 to 125.5°C. Biotest Example : Comparative compound (C-1, C-2 and C-3 are similar to the compounds covered by those disclosed in Japanese Patent Application Disclosure No. Sho-60-146879 (1985)) Test Example 3 (Biotest example) Test on herbicidal activity against lowland weeds Formulation of Active Compounds Carrier : 5 parts by weight of acetone Emulsifier : 1 part by weight of benzyloxy polyglycol ether To produce a suitable preparation of each of the active compounds, 1 part by weight of an active compound was mixed with the stated amount of carrier and with the stated amount of emulsifier, and the resulting emulsifiable concentrate was then diluted with water to the desired concentrations. Test Procedures Aquatic paddy soil was filled in pots (1/2,000 ares, 25 x 20 x 9 cm), and rice seedlings (variety: Nipponbare) in the 2.5 leaf stage (plant height about 15 cm) were transplanted in two spots at a rate of three per hill. Seeds of Echinochloa crus-galli P. B. var. oryzoides Ohwi, Cyperus difformis L., Scirpus juncoides Roxb., Monochoria vaginalis Presl., and annual broad-leaved weeds such as Lindernia pyxidaria L., Rotala indica Koehne, Elatine triandra Schk., Ammannia multiflora Roxb., Dopatrium junceum Hamilt. and so on were inoculated in the pots. The soil in the pots was maintained in wet state. Two days after, each pot was watered to a depth of about 2 to 3 cm. Five days after the transplantation of the rice seedlings, a predetermined amount of the compounds in the form of an emulsion, prepared in the manner mentioned above was applied on the water-surface of each pot by means of a pipette. After the treatment, each pot was maintained in the watered state to a depth of about 3 cm. In the three week after the treatment, the herbicidal effect and the degree of phytotoxicity were evaluated, wherein 100% indicates the complete death and 0% indicates no herbicidal effect. The results are shown in Table 2. Compound Dosage of Active Compound (kg/ha Herbicidal effect (%) Phytotoxicity (%) Echinochloa Cyperus Scirpus Monochoria Broad leaf weeds Rice Oryza 2 0.3 100 100 100 100 100 5 0.2 100 100 90 100 90 0 3 0.3 100 100 100 100 100 0 0.2 100 100 90 100 90 0 4 0.3 100 100 100 100 100 0 0.2 100 100 90 100 90 0 5 0.3 100 100 100 100 100 0 0.2 100 100 90 100 80 0 Comparative C-1 0.3 90 100 80 90 60 15 0.2 80 90 70 80 50 10 C-2 0.3 90 100 70 90 40 10 0.2 60 90 40 60 30 5 C-3 0.3 80 100 70 80 40 15 0.2 60 80 40 50 30 10 Example 4 (Biotest) Test for determining herbicidal effect of the present herbicidal compositions on lowland weeds In a greenhouse, aquatic paddy soil was filled in pots (1/2,000 ares, 25x20x9 cm), and rice seedlings ( cv. Nipponbare) in the 2.5 leaf stage with a height of 15 cm were transplanted in two spots into the pot at a rate of three per hill. Then, the tubers of Sagittaria pygmaea Miq and small pieces of Spikerrush (Eleocharis acicularis) as well as the seeds of the following respective weeds were inoculated into the respective pots and filled with water to a height of about 2 to 3 cm above the soil surface: Echinochloa orizicola vasing, Cyperus difformis L., Monochoria vaginalis Presl, Broad leaved weeds such as Lindernia pyxidaria, Rotala indica Koehne, American waterwort (Elatine orientalis Makino), Ammannia multiflora Roxburgh, Dopatrium junceum Hamilton, Bulrush, Scirpus juncoides and Roxburgh. Five days after the transplantation of the rice seedling, a predetermined amount of the active compounds in the form of an emulsion which had been prepared in the manner mention ed above, was applied on water-surface of each pot. After that, water depth in each pot was maintained at about 3 cm. Three weeks after application of the active compound, the herbicidal effect and the degree of phytotoxicity were deter mined according to the following rating system,wherein 100% indicates the complete death and 0% indicates no herbicidal effect. The results will be shown in the following Table 3: In Table 3, A, B, C, D, E, F and G in the herbicidal compositions under test represent the following active compounds, respectively: A : Methyl 2-[3-(4,6-dimethoxypyrimidin -2-yl)ureidosulfonylmethyl] benzoate, B : Ethyl 5-[3-(4,6-dimethoxypyrimidin -2-yl)ureidosulfonyl]-1-methylpyrazole-4-carboxylate, C : N-(2-chloroimidazole[1,2-a]pyridin -3-yl-sulfonyl)-N'-(4,6-dimethoxy-2-pyrimidyl) urea, D : 4-(2,4-dichlorobenzoyl)-1,3-dimethyl-5-pyrazolyl-p-toluenesulfonate, E : 2-(β-naphthyloxy) propionailide, F : 2-ethylamino-4-(1,2-dimethyl propylamino)-6-methylthio-1,3,5-triazine, G : S-p-chlorobenzyl diethylthiocarbamate. In Table 3, the composition indicated by (*1) controlled the emergence of Barnyard grass (Echinochloa) for a period of forty-eight days, while the compound No. 4 indicated by (*2) controlled said emergence for a period of forty days, and the compound G (*3) controlled said emergence for a period of twenty-five days. Formulation Example 1 Water was added to a mixture consisting of 1 part by weight of the above-mentioned active compound No.1, 0.25 parts by weight of the above-mentioned active compound A, 30 parts by weight of bentonite, 66.75 parts by weight of talc, and 2 parts by weight of lignin sulfonate, followed by an intimate kneading, granulating and drying to obtain granules.

Claims: Novel tetrazolinones of the formula (I) wherein X represents chloro, Y represents hydrogen atom, chloro, or methyl, R 1 represents ethyl or n-propyl, and R 2 represents cyclopentyl or cylohexyl, with the proviso that the total of the carbon atoms of R 1 and R 2 is 7 or 8. The compounds of the formula (I) according to claim 1 wherein X represents chloro, Y represents hydrogen atom, or methyl, R 1 represents ethyl or n-propyl, and R 2 represents cyclopentyl or cyclohexyl,with the proviso that the total of the carbon atoms of R 1 and R 2 is 7 or 8. A compound according to claim 1, wherein such compound is 1-(2-chlorophenyl)-4-(N-cyclohexyl-N-ethylcarbamoyl)-5(4H) -tetrazolinone of the formula: or 1-(2-chloro-6-methylphenyl)-4-(N-cyclopentyl-N-n-propylcarbamoyl)-5(4H)-tetrazolinone of the formula: A process for the preparation of the compounds of the formula (I) wherein X represents chloro, Y represents hydrogen atom, chloro, or methyl, R 1 represents ethyl or n-propyl, and R 2 represents cyclopentyl or cylohexyl, with the proviso that the total of the carbon atoms of R 1 and R 2 is 7 or 8, characterized in that a) compounds of the formula (II) wherein X and Y have the same meanings as mentioned before, are reacted with compounds of the formula (III) wherein R 1 and R 2 have the same meanings as mentioned above, and hal is an eliminating group such as chlorine or bromine, in the presence of inert solvents, and if appropriate, in the presence of an acid binder. Herbicidal compositions against paddy weeds, characterized in that they contain at least one tetrazolinone of the formula (I) according to claim 1. Process for combatting paddy weeds, characterized in that tetrazolinones of the formula (I) according to claim 1 are allowed to act on weeds and/or their habitat. Use of tetrazolinones of the formula (I) according to claim 1 for combatting paddy weeds. Process for the preparation of herbicidal compositions against paddy weeds, characterized in that tetrazolinones of the formula (I) according to claim 1 are mixed with extenders and/or surface-active agents. Mixed herbicidal compositions against paddy weeds which comprise containing tetrazolinones of the formula (I) according to claim 1 and at least one active compound selected from the group consisting of herbicidal sulfonamides, herbicidal pyrazoles, herbicidal propionanilides, herbicidal triazines, herbicidal carbamates, herbicidal diphenylethers, and herbicidal acid amides. Mixed compositions according to claim 9, wherein the herbicidal sulfonamides are one or more of the compounds including N-2-biphenylylsulfonyl N'-(4,6-dimethoxy-1,3,5-triazin -2-yl)urea, ethyl 5-[3(4,6-dimethoxypyrimidin -2-yl) ureidosulfonyl]-1-methylpyrazole-4-carboxylate, methyl 2-[3-(4,6-dimethoxypyrimidin -2-yl) ureidosulfonylmethyl] benzoate, 3-(4,6-dimethoxy-1,3,5-triazin -2-yl)-1-[2-(2-methoxyethoxy)phenylsulfonyl]urea, N-(2-chloroimidazole[1,2-a]pyridin -3-yl-sulfonyl)-N'-(4,6-dimethoxy-2-pyrimidyl)urea, N'-(4,6-dimethoxypyrimidin -2-yl)-N''-(4-methylphenylsulfonylamino)-N'''-(4-ethoxycarbonyl-1-methylpyrazol -5-yl-sulfonyl)guanidine, and N-(2-cyclopropylcarbonylphenylsulfamoyl)-N'-(4,6-dimethoxypyridin -2-yl)urea. Mixed compositions according to claim 9, wherein the herbicidal pyrazoles are one or more of the compounds including 4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol -5-yl-p-toluene sulfonate, 2-[4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol -5-yl]acetophenone, and 2-[4-(2,4-dichloro-m-toluoyl)-1,3-dimethylpyrazol -5-yloxy]-4-methylacetophenone. Mixed compositions according to claim 9, wherein the herbicidal propionanilides are one or more of the compounds including 2-(β-naphthyloxy)propione anilide and (RS)-2-(2,4-dichloro-m-tolyloxy)propione anilide. Mixed compositions according to claim 9, wherein the herbicidal triazines are one or more of the compounds including 2,4-bis(ethylamino)-6-(methylamino)-1,3,5-triazine and 2-ethylamino-4-(1,2-dimethylpropylamino)-6-methylthio-1,3,5-triazine. Mixed compositions according to claim 9, wherein the herbicidal carbamates are one or more of the compounds including S-p-chlorobenzyl diethylthiocarbamate, S-1-methyl-1-phenylethyl piperidine-1-carbothioate, and S-benzyl 1,2-dimethyl-propyl(ethyl)thiocarbamate. Mixed compositions according to claim 9, wherein the herbicidal diphenylethers are one or more of the compounds including 2,4,6-trichlorophenyl-4'-nitrophenylether, and 2,4-dichlorophenyl-3'-methoxy-4-nitrophenylether. Mixed compositions according to claim 9, wherein the herbicidal acid amides are (RS)-2-bromo-N-(α,α-dimethylbenzyl)-3,3-dimethylbutylamide. Mixed compositions according to claim 9, which comprise per one part by weight of the novel tetrazolinones as claimed in the claim 1, 0.01 to 2 parts by weight of herbicidal sulfonamides, 2.5 to 35 parts by weight of herbicidal pyrazoles, 0.6 to 50 parts by weight of herbicidal propionanilides, 0.06 to 10 parts by weight of herbicidal triazines, 3 to 15 parts by weight of herbicidal carbamates, 5 to 35 parts by weight of herbicidal diphenylethers, and/or 3.5 to 25 parts by weight of herbicidal amides.

Inventors: GOTO TOSHIO, ITO SEISHI, NARABU SHIN-ICHI, WATANABE YUKIYOSHI, YANAGI AKIHIKO, GOTO, TOSHIO, ITO, SEISHI, NARABU, SHIN-ICHI, WATANABE, YUKIYOSHI, YANAGI, AKIHIKO
Applicants: BAYER AGROCHEM KK, NIHON BAYER AGROCHEM K.K.
Application year: 1994
Main classification: C07D257
IPC codes: A01N47, C07D257